1. Field
The described technology relates generally to a system and method for cleaning a substrate.
2. Description of Related Art
A flat panel display is a thin display device having a flat panel and being relatively thin with respect to other display devices. Typical examples of a flat panel display include a liquid crystal display (LCD), a plasma display device, an organic light emitting diode (OLED) display, etc.
A flat panel display includes a display panel for displaying an image, and in order to manufacture such a display panel, various processes, for example, an etching process and a cleaning process are performed.
Particularly, when cleaning a silicon oxide film on an amorphous silicon layer that is formed in the OLED display or a silicon oxide film on a polysilicon layer, a spin cleaning method, or a track cleaning method of spraying a hydrofluoric acid (HF) cleaning liquid to a substrate on an in-line with a spray method or of flowing a hydrofluoric acid cleaning liquid with a flow method is used.
However, as the OLED display is formed in relatively larger sizes, in a spin cleaning method, it is difficult to rotate a substrate in a high speed, and in a track cleaning method, etching uniformity is difficult due to an etching difference between an intermediate portion and an edge portion of a substrate, and thus a crystallization process of an amorphous silicon layer, which follows the etching and an interface between a polysilicon layer and a gate insulating layer are affected, whereby a problem such as a crystallization stain and an element failure occurs.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the described technology and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.